A radiation-hardened-by-design phase-locked loop (PLL) with a frequency range of 200 to 1000 MHz is proposed. By presenting a novel charge compensation circuit, composed by a lock detector circuit, two operational amplifiers, and four MOS devices, the proposed PLL significantly reduces the recovery time after the presence of a single event transient (SET). Comparing with many traditional hardened methods, most of which endeavor to enhance the immunity of the charge pump output node to an SET, the novel PLL can also decrease its susceptibility in the presence of an SET in other blocks. A novel system model is presented to describe immunity of a PLL to an SET and used to compare the sensitivity of traditional and hardened PLLs to an SET. An SET is simulated on Sentaurus TCAD simulation workbench to model the induced pulse current. Post simulation with a 130 nm CMOS process model shows that the recovery time of the proposed PLL reduces by up to 93.5% compared with the traditional one, at the same time, the charge compensation circuit adds no complexity to the systemic parameter design.

A novel 8T single-event-upset (SEU) hardened and high static noise margin (SNM) SRAM cell is proposed. By adding one transistor paralleled with each access transistor, the drive capability of pull-up PMOS is greater than that of the conventional cell and the read access transistors are weaker than that of the conventional cell. So the hold, read SNM and critical charge increase greatly. The simulation results show that the critical charge is almost three times larger than that of the conventional 6T cell by appropriately sizing the pull-up transistors. The hold and read SNM of the new cell increase by 72% and 141.7%, respectively, compared to the 6T design, but it has a 54% area overhead and read performance penalty. According to these features, this novel cell suits high reliability applications, such as aerospace and military.

This paper presents the design and implementation of a monolithic CMOS DC-DC boost converter that is hardened for total dose radiation. In order to improve its radiation tolerant abilities, circuit-level and devicelevel RHBD (radiation-hardening by design) techniques were employed. Adaptive slope compensation was used to improve the inherent instability. The H-gate MOS transistors, annular gate MOS transistors and guard rings were applied to reduce the impact of total ionizing dose. A boost converter was fabricated by a standard commercial 0.35 m CMOS process. The hardened design converter can work properly in a wide range of total dose radiation environments, with increasing total dose radiation. The efficiency is not as strongly affected by the total dose radiation and so does the leakage performance.

A high sensitivity navigation receiver based on FPGA and DSP was presented in this paper, which performed to mitigate cross correlations between multiple satellite signals. The hardware was consisted of RF parts, FPGA and DSP. The core chips were SPARTAN3 and TMS320VC5402, which were adapted to process navigation data and calculate user position. The RF Front-End received the navigation signal and convert it to IF signal which was transferred to FPGA. The algorithm of acquisition and tracking of navigation signal were implemented with SPARTAN3. A parallel correlator using three local replica C/A code was developed here, which improved the acquiring efficiency. This system calculated the user position by TMS320VC5402.

To achieve a constant current limit, low power consumption and high driving capability, a micro-power LDO with a piecewise voltage-foldback current-limit circuit is presented. The current-limit threshold is dynamically adjusted to achieve a maximum driving capability and lower quiescent current of only 300 nA. To increase the loop stability of the proposed LDO, a high impedance transconductance buffer under a micro quiescent current is designed for splitting the pole that exists at the gate of the pass transistor to the dominant pole, and a zero is designed for the purpose of the second pole phase compensation. The proposed LDO is fabricated in a BiCMOS process. The measurement results show that the short-circuit current of the LDO is 190 mA, the constant limit current under a high drop-out voltage is 440 mA, and the maximum load current under a low drop-out voltage is up to 800 mA. In addition, the quiescent current of the LDO is only 7 A, the load regulation is about 0.56% on full scale, the line regulation is about 0.012%/V, the PSRR at 120 Hz is 58 dB and the drop-out voltage is only 70 mV when the load current is 250 mA.